From e7eb2db06d1b9c529f94f2da3a087c83c0498e05 Mon Sep 17 00:00:00 2001 From: Cliff Click Date: Mon, 19 Oct 2026 10:40:35 -0700 Subject: Turn off Store GVN with explaination --- .../java/com/seaofnodes/simple/Chapter10Test.java | 24 ++++++++++++++++++++-- 1 file changed, 22 insertions(+), 2 deletions(-) (limited to 'chapter13/src/test') diff --git a/chapter13/src/test/java/com/seaofnodes/simple/Chapter10Test.java b/chapter13/src/test/java/com/seaofnodes/simple/Chapter10Test.java index 6649c0b0..7fa9978d 100644 --- a/chapter13/src/test/java/com/seaofnodes/simple/Chapter10Test.java +++ b/chapter13/src/test/java/com/seaofnodes/simple/Chapter10Test.java @@ -11,6 +11,26 @@ import static org.junit.Assert.assertEquals; import static org.junit.Assert.fail; public class Chapter10Test { + @Test public void testConditionalStoreSharing() { + // Sharing the writes on two of three paths must not write on the third. + // Return the object so Load forwarding cannot hide the physical Store. + String src = """ + struct S { int x; }; + S a = new S; + a.x = 10; + if (arg == 1) a.x = 9; + else if (arg == 2) a.x = 9; + return a; + """; + var stop = new Parser(src).parse().iterate(); + for( int arg : new int[]{0,1,2,3} ) { + long expected = (arg==1 || arg==2) ? 9 : 10; + var obj = (com.seaofnodes.simple.evaluator.Evaluator.Obj) + com.seaofnodes.simple.evaluator.Evaluator.evaluate(stop,arg); + assertEquals(expected,obj.fields()[0]); + } + } + @Test public void testDeadReferenceReturn() { for( String body : new String[] { "return new S; return 0;", @@ -540,14 +560,14 @@ return 0; assertEquals(3L,Evaluator.evaluate(stop,3)); } - @Test public void testDropStores() { + @Test public void testKeepBranchStores() { StopNode stop = new Parser(""" struct S { int x; } S s = new S; if (arg) s.x=arg+1; else s.x=arg+2; return s; """).parse().iterate(); - // These chapters still bind struct Stores to branch control. + // Two branch Stores plus the initial zero Store. assertEquals(3,countMemoryNodes(stop,StoreNode.class,new BitSet())); assertEquals(2L,((Evaluator.Obj)Evaluator.evaluate(stop,0)).fields()[0]); assertEquals(4L,((Evaluator.Obj)Evaluator.evaluate(stop,3)).fields()[0]); -- cgit v1.2.3